1. Field of the Invention
The present invention relates generally to movable extension units for creating additional interior space within a structure providing living space. More particularly, the invention relates to movable extension units for recreational vehicles, manufactured housing, and specialty trailers.
2. Description of the Related Art
Physical dimensional restrictions limit the amount of interior space within many structures providing living space. For example, recreational vehicles, manufactured housing, and specialty trailer structures are restricted in their width dimension because of space restrictions upon the highways upon which those structures are transported. However, once the recreational vehicle, manufactured housing, or specialty trailer component has completed its transport, either temporarily or permanently, the structure no longer has a width restriction. In fact, the occupants of those structures would prefer to have a greater amount of interior living space.
To accommodate the desire for additional interior space, several different configurations have been employed. One example involves creating a pop-out compartment formed by the extension of side walls from the recreational vehicle. In the side walls' retracted position, the side walls form interior partitions within the vehicle. These interior partitions limit the amount of interior space within the vehicle when the compartment is retracted.
Another example involves a tent camper with a lateral slide-out room. The tent camper includes a camper main body that is pulled in a longitudinal direction by a towing vehicle. A roof, aligned above the camper main body, is movable between a lowered, storage or transport position and a raised, camping or deployed position. The lateral slide-out room, coupled to the camper body, is movable in a lateral direction between a retracted, storage position and an extended, operational position. This allows the lateral slide-out to extend and provide additional living space within the camper. The interior space of the camper is not habitable in the retracted, transport position, the overlap or interior partition of the slide-out side walls within the camper is not an issue.
A further example involves a mobile accommodation structure such as a caravan or motor home with a foldable extension for enlarging the volume of the vehicle. A wall panel is attached to guide rails on the side of the vehicle for pivotal and sliding movement over the vehicle side wall. Another wall panel is only pivotally connected to the side wall, while the middle wall panel is pivotally connected to both other wall panels. The roof of the accommodation structure is hinged on the vehicle roof edge to be able to move from a position overlying the vehicle roof to a position covering the trapezoidal recess formed by the side walls when deployed. The floor is hinged on the floor edge so that it is capable of moving from a position parallel to the vehicle side wall to a position co-planar with the vehicle floor.
Each of these prior structures includes drawbacks in terms of the use and reliability of the extension unit. In most recreational vehicles, the creation of interior partitions in the retracted position diminishes the utility of the extension, as often such interior partitions interfere with the amount of the space within the vehicle during transport, either as living or storage space. The deployment mechanisms, such as the pivotal and sliding connection on the body of a recreational vehicle, require manufacturing complication and expense to create the extension unit. Also, the movable connections of the wall panels with the vehicle require seals to prevent the penetration of moisture and the elements into the interior region. Finally, the difficulty of deploying the additional interior space often involves complex mechanisms requiring application of significant force on the mechanism. However, for convenience of use, units which may be deployed using only the equipment associated with the structure are preferred.
What is needed in the art is an extension unit which provides the desired additional interior space without creating interior partitions, which minimizes leakage points into the interior space, and which accomplishes these goals with a minimal increase in complication and expense.